Apparatus for winding thread on a bobbin



June 11, 1935. s. w. BRAINARD 2,004,153

APPARATUS FOR WINDING THREAD ON A BOBBIN Filed Oct. 22, 1931 a nven'tot.

J e yin our wilaon .Brainard Patented June 11, 1935 v UNITED STATESPATENT OFFICE APPARATUS FOR WINDING THREAD ON A BOBBIN Seymour WilsonBrainard, Kenmore, N. Y., as-

signor to Du Pont Rayon Company, New York,

N. Y., a corporation of Delaware Application October 22, 1931, SerialNo. 570,476

' 2 Claims. (01. 242-l8) wherein the thread is twisted and wound upon abobbin before being subjected to treatment by liquids. The inventionwill be described as applied to the manufacture of viscose rayon,although it is equally applicable to other forms of rayon and to thewinding of difierent classes of thread.

In the manufacture of artificial thread from viscose by the bobbinprocess the thread is wound on a bobbin in untwisted condition and isrewound upon a second bobbin with twisting. The

rewinding bobbin is usually surface driven, that is to say, it is drivenby the contact of the yarn mass with a rotating roller covered with arelatively dense material such as leather or cork. It is the experienceof rayon manufacturers that the thread cakes produced by this method aredense, hard, and difficult to treat with liquids; that they have hardends; and that the cakes formed by this process often have particularareas which are considerably harder than .the remainder of the cake.Such cakes cannot be thoroughly purified without the use of excessiveamounts of purifying liquid and the expenditure of exceedingly longperiods of time. More important, they cannot be uniformly purified evenwhen the treatment is sufficiently strenuous to risk degrading the yarn.

An object of this invention is to wind thread into a soft, uniformlyliquid-permeable cake. Another object of the invention is to wind rayoninto an easily purifiable package. Another object of the invention is toprovide an improved winding machine. Other objects of the invention willbe in part apparent and in part described in the followingspecification.

I have discovered that the building up of a hard cake is due, ingeneral, to the fact that the thread on the rewind bobbin makes contactwith the driving roller in a band so narrow as to amount almost toa lineparallel to the axis of the bobbin. The pressure due to the weight ofthe rewinding bobbin is, consequently, relatively large per unit area.This pressure causes the formation of a dense, hard cake.

I have also discovered that the formation of hard spots in the cake isdue to the inequalities I the rewound cake are formed because more yarnis laid down at the ends than at any other portion of the bobbin due tothe reversal of direction of the traverse guide and thread lag betweenit and the point at which the thread winds onto the bobbin. Since thereis more yarn at the ends the weight of the bobbin is borne more by theends than by the balance of the cake and tightly packed ends result.

The objects of this invention are accomplished, generally speaking, bysubstantially increasing the area of contact between the thread on therewind bobbin and the driving roller. The objects of the invention areaccomplished, more specifically speaking, by the invention hereindescribed and claimed.

In the drawing, Fig. 1 is an elevational view of a set up for twistingand rewinding; Fig. 2 is a front elevation, showing the rewindingmechanism; Fig. 3 shows a rewinding mechanism with a modified form ofdriving roller.

In the drawing, numeral I is a bobbin of rayon;

2 is a diagrammatic representation of a thread guide; 3 is the rayonthread; 4 is a guide for traversing the thread from end to end of thebobbin; 5 is a rewind bobbin;. 6 is a roller for driving the rewindbobbin; 1 is a surface on the rewind roller of soft, yieldable materialsuch as sponge rubber. V

Other yieldable materials than soft rubber may be used to surface theroller and act as a broad support and shock absorber between the driveroll' and the rewind bobbin. Felt, various artificial resinous bodies,and loosely wound layers of artificial silk or other yarn are examplesof such materials.

Advantage can be secured by altering the shape of the driving roller asshown in Fig. 3, wherein BI is a roller covered with yieldable -materialwhose central portion alone contacts with the material on the bobbin. Bythe use of this modification, a cake-of yarn is secured which has softand easily processed ends.

An advantage of my invention .is the ability to wind 9. soft package ofyarn. Another advantage of my invention is in the ability to wind 9.

cake of yarn which may be easily, quickly, and uniformly purified.Another advantage is in the preparation of a package so loosely woundthat shrinkage may take place without setting up strains which degradethe yarn. Other advantages of the invention will be apparent.

As many apparently widely different embodiments of' this invention maybe made without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myself to the face in driving contact.with the material wound specific embodiments thereof except as definedin thereon.

the appended claims. 2. In the manufacture of rayon, a winding bob 1claim: bin, and a roller having a sponge rubber surface v I 1. In themanufacture of rayon, a winding bobin driving relation to the centerthereof. 5

bin, and a roller having a soft and yieldable sur- SEYMOUR W. BRAINARD.

